Continuously variable transmission

ABSTRACT

A continuously variable transmission. The transmission includes a plurality of power adjusters, such as spherical balls, frictionally interposed between a driving and a driven member. The driving and the driven member are each rotatably disposed over a main shaft. The spherical balls are configured to rotate about a modifiable axis and thereby provide a continuously variable shifting capability by adjusting the ratio between the angular velocity of the driving member in relation to the driven member. The system includes automatic and manual shifting gearing for adjusting the speed of the transmission. The system also includes a support a support member which is rotatably disposed over the main shaft and frictionally engaged to each of the spherical balls.

RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.09/823,620, filed Mar. 30, 2001 now U.S. Pat. No. 6,322,475, which is acontinuation of U.S. application Ser. No. 09/133,284, filed Aug. 12,1998 now U.S. Pat. No. 6,241,636, which in turn claims priority to U.S.Provisional Application No. 60/062,860, filed on Oct. 16, 1997; U.S.Provisional Application No. 60/056,045, filed on Sep. 2, 1997; U.S.Provisional Application No. 60/062,620, filed on Oct. 22, 1997 and U.S.Provisional Application No. 60/070,044 filed on Dec. 30, 1997, all ofwhich are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The field of the invention relates to transmissions. More particularlythe invention relates to continuously variable transmissions.

2. Description of the Related Art

In order to provide an infinitely variable transmission, varioustraction roller transmissions in which power is transmitted throughtraction rollers supported in a housing between torque input and outputdisks have been developed. In such transmissions, the traction rollersare mounted on support structures which, when pivoted, cause theengagement of traction rollers with the torque disks in circles ofvarying diameters depending on the desired transmission ratio.

However, the success of these traditional solutions have been limited.For example, in U.S. Pat. No. 5,236,403 to Schievelbusch, a driving hubfor a vehicle with a variable adjustable transmission ratio isdisclosed. Schievelbusch teaches the use of two iris plates, one on eachside of the traction rollers, to tilt the axis of rotation of each ofthe rollers. However, the use of iris plates can be very complicated dueto the large number of parts which are required to adjust the irisplates during shifting the transmission. Another difficulty with thistransmission is that it has a guide ring which is configured to bepredominantly stationary in relation to each of the rollers. Since theguide ring is stationary, shifting the axis of rotation of each of thetraction rollers is difficult. Yet another limitation of this design isthat it requires the use of two half axles, one on each side of therollers, to provide a gap in the middle of the two half axles. The gapis necessary because the rollers are shifted with rotating motioninstead of sliding linear motion. The use of two axles is not desirableand requires a complex fastening system to prevent the axles frombending when the transmission is accidentally bumped, is as often thecase when a transmission is employed in a vehicle. Yet anotherlimitation of this design is that it does not provide for an automatictransmission.

Therefore, there is a need for a continuously variable transmission witha simpler shifting method, a single axle, and a support ring having asubstantially uniform outer surface. Additionally, there is a need foran automatic traction roller transmission which is configured to shiftautomatically. Further, the practical commercialization of tractionroller transmissions requires improvements in the reliability, ease ofshifting, function and simplicity of the transmission.

SUMMARY OF THE INVENTION

The present invention includes a transmission, comprising three or morespherical power adjusters, each power adjuster having a cylindrical holeextending through its center and three or more cylindrical spindles witheach spindle positioned in the hole of one power adjuster. There may beat least one stationary support with an aperture at its center and arotatable support member having first and second sides. The rotatablesupport member can be located between the power adjusters andfrictionally engaged with the plurality of power adjusters. Therotatable support member can have a substantially uniform outerdiameter, and is capable of axial movement. The rotatable support membermay have at least two areas that are bearing surfaces to control axialmovement of the rotatable support member. Interacting with the rotatablesupport member is a first annular bearing, capable of axial movement, ispositioned on the first side of the support member and a second annularbearing capable of axial movement, positioned on the second side of thesupport member. A first planar platform capable of axial movement, ispositioned so that the first annular bearing is between the rotatablesupport member and the first planar platform. A second planar platform,capable of axial movement, is positioned so that the second annularbearing is between the rotatable support and the second planar platform.A ratio changer operably connected to the cylindrical spindles causesthe cylindrical spindles to change their axes of rotation.

One embodiment includes a transmission, comprising a drive sleeve withthree or more ramped surfaces on the drive sleeve that face therotatable driving member. Three or more rollers are positioned to rollon the three or more ramped surfaces of the drive sleeve and also rollon the rotatable driving member. A roller cage positions the three ormore rollers. The three or more ramped surfaces of the drive sleeve areconfigured so that when the three or more rollers rotate they compressthe rotatable driving member against the three or more spherical poweradjusters upon an increase in torque and decompress the rotatabledriving member upon a decrease in torque. The embodiment may have atleast one stationary support with an aperture at its center.

Yet another embodiment includes a plurality of legs rigidly attached tothe at least one stationary support. The plurality of legs extend in adirection from the at least one stationary support towards the sphericalpower adjusters. The plurality of legs are designed to assist in holdingthe spherical power adjusters in a stationary position.

Another embodiment includes a shifting member having an end that extendsoutside of the transmission. The shifting member is positioned along theaxis of the rotatable support member and is operably engaged with therotatable support member. An adjustment in the position of the shiftingmember causes the rotatable support member, the first annular bearing,the second annular bearing, the first planar platform, and the secondplanar platform to all move simultaneously and a substantially equaldistance.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partial perspective view of the transmission of the presentinvention.

FIG. 2 is a partial exploded view of the transmission of FIG. 1.

FIG. 3 is an end cutaway elevational view of the transmission of FIG. 1.

FIG. 4 is a cutaway side elevational view of the transmission of FIG. 1.

FIGS. 5 and 6 are cutaway side elevational views of the transmission ofFIG. 1 illustrating the transmission of FIG. 1 shifted into differentpositions.

FIG. 7 is an end cutaway view of an alternative embodiment of thetransmission of the invention wherein the transmission shiftsautomatically.

FIG. 8 is a side elevational view of the transmission of FIG. 7.

FIG. 9 is an end cutaway view of an alternative embodiment of thetransmission of the invention wherein the transmission includes astationary hub shell.

FIG. 10 is a cutaway side elevational view of the transmission of FIG.9.

FIG. 11 is a cutaway side elevational view of an alternative embodimentof the transmission of FIG. 1 wherein the transmission has two thrustbearings.

FIG. 12 is a cutaway side elevational view of an alternative embodimentof the invention wherein a first and second one way rotatable driverprovides an input torque to the transmission.

FIG. 13 is a schematic cutaway end elevational view of anotheralternative embodiment of the transmission of the invention.

FIG. 14 is a schematic cutaway front elevational view of thetransmission of FIG. 13.

FIG. 15 is a schematic end view of a housing for the transmission ofFIGS. 13 and 14.

FIG. 16 is a schematic cutaway front elevational view of anotheralternative embodiment of the transmission of the invention.

FIG. 17 is a side elevational view of an alternative embodiment of asupport member.

DETAILED DESCRIPTION OF THE INVENTION

The following detailed description is directed to certain specificembodiments of the invention. However, the invention can be embodied ina multitude of different ways as defined and covered by the claims. Inthis description, reference is made to the drawings wherein like partsare designated with like numerals throughout.

The present invention includes a continuously variable transmission thatmay be employed in connection with any type of machine that is in needof a transmission. For example, the transmission may be used in (i) amotorized vehicle such as an automobile, motorcycle, or watercraft, (ii)a non-motorized vehicle such as a bicycle, tricycle, scooter, exerciseequipment or (iii) industrial power equipment, such as a drill press.

FIGS. 1 through 4 disclose one embodiment of the present invention. FIG.1 is a partial perspective view of a transmission 100. FIG. 2 is anexploded view of the transmission 100 of FIG. 1. FIG. 3 shows a partialcross sectional end view of the transmission 100. FIG. 4 shows a cutawayside elevational view of the transmission 100.

Referring generally to FIGS. 1 through 4, a hollow main shaft 102 isaffixed to a frame of a machine (not shown). The shaft 102 may bethreaded at each end to allow a fastener (not shown) to be used tosecure the transmission 100 on the main shaft 102 and/or to attach themain shaft 102 to a machine. A rotatable driver 401 (FIG. 4) comprisinga sprocket or a pulley is rotatably affixed to the main shaft 102, so asto provide an input torque to the transmission 100. A drive sleeve 104is coaxially coupled to the rotatable driver 401 (FIG. 4) and rotatablydisposed over the main shaft 102. A surface 106 (FIG. 2) of the drivesleeve 104 opposite the rotatable driver 401 (FIG. 4), can include aplurality of shallow grooves 108.

A first roller cage assembly 110 is coaxially coupled to the drivesleeve 106 opposite the rotatable driver 401 and also rotatably disposedover the main shaft 102. The first roller cage assembly 110 has aplurality of cylindrical rollers 112 radially arranged about a midpointof the roller cage assembly 110. Each of the cylindrical rollers 112 arerotatably mounted on the first roller cage assembly 110 such that eachof the rollers may rotate about its lengthwise axis. Preferably, aone-to-one correlation exists between each of the shallow grooves 108and each of the cylindrical rollers 112. Optionally, the cylindricalrollers 112 may be replaced with rollers of an alternative geometricshape, such as with spherical rollers.

A tension inducer 118 (FIG. 2), such as a spring, is rotatably disposedover the main shaft 102 and frictionally coaxially coupled to the firstroller cage assembly 110 opposite to the drive sleeve 104. Further, arotatable driving member 120 is rotatably affixed to the main shaft 102and coaxially coupled to a side of the first roller cage assembly 110opposite the drive sleeve 104. A surface 107 (FIG. 4) of the rotatabledriving member 120 opposed to the drive sleeve 104 includes a pluralityof shallow grooves 109 (FIG. 4). Relative rotation of the roller cage110 with respect to the drive sleeve 104 causes the cylindrical rollers112 to roll on the shallow grooves 108, 109 and move the shallow grooves108, 109 toward or away from each other along the axis of the main shaft102.

A plurality of spherical power adjusters 122A, 122B, 122C are infrictional contact with a side of the rotatable driving member 120opposite the roller cage assembly 110. In one embodiment of theinvention, the power adjusters 122A, 122B, 122C are spheres made ofhardened steel; however, the power adjusters 122A, 122B, 122C mayalternatively include other shapes and be manufactured from othermaterials. A plurality of spindles 130A, 130B, 130C (FIG. 2)respectively extend through multiple passages 128A, 128B, 128C (FIG. 2)in the power adjusters 122A, 122B, 122C. Radial bearings (not shown) maybe disposed over each of the spindles 130A, 130B, 130C (FIG. 2) tofacilitate the rotation of the power adjusters 122A, 122B, 122C.

A plurality of pivot supports 134A, 134B, 134C respectively hold thespindles 130A, 130B, 130C (FIG. 2). The support 134A includes two legs135A and 137A for connection to a ratio changer 166 which is discussedin further detail below. Similarly, the support 134B includes two legs135B and 137B, and the pivot support 134C includes two legs 135C and137C.

The pivot supports 134A, 134B, 134C respectively include pivot rings136A, 136B, 136C. The pivot ring 136A has four apertures 138A, 140A,142A, 144A (FIG. 2). Similarly, the pivot support 134B has fourapertures 138B, 140B, 142B, and 144B, and the pivot support 134C hasfour apertures 138C, 140C, 142C, and 144C (FIG. 2). The apertures 138A,138B, 138C are respectively located opposite to the apertures 140A,140B, 140C on the pivot rings 136A, 136B, and 136C. Together, theapertures 138A, 138B, 138C, and the apertures 140A, 140B, 140C arerespectively configured to receive the spindles 130A, 130B, 130C (FIG.2).

The apertures 142A, 142B, 142C (FIG. 2) are respectively locatedopposite to the apertures 144A, 144B, 144C (FIG. 2) on the pivot rings136A, 136B, 136C. Together, the apertures 142A, 142B, 142C and theapertures 144A, 144B, 144C are configured to receive multipleimmobilizers 150A, 150B, 150C (FIG. 2). In one embodiment of theinvention, the immobilizers 150A, 150B, 150C are each cylindrical rigidrods, slightly angled at each end. A central portion of each of theimmobilizers 150A, 150B, 150C are affixed to one of multiple legs 153(FIG. 2) of a stationary support 152 (FIG. 2). The stationary support152 is fixedly attached to the main shaft 102.

A support member 154 is slidingly and rotatably disposed over the mainshaft 102 proximate to a side of the stationary support 152 (FIG. 2)which is opposite to the rotatable driving member 120. The supportmember 154 is in frictional contact with each of the power adjusters122A, 122B, 122C. In one embodiment of the invention, the support member154 is a cylindrical ring having a substantially uniform outercircumference from an end cross-sectional view. In another embodiment ofthe invention, the support member 154 is a cylindrical ring having afirst and second flange (not shown) which respectively extend radiallyoutwardly from a first and second end of the support member 154 so as toprevent the power adjusters 122A, 122B, 122C from disengaging from thesupport member 154. In yet another embodiment of the invention, thesupport member 154 is a cylindrical ring having a nominally concavicalouter surface (FIG. 17).

The support member 154 may contact and rotate upon the main shaft 102,or may be suspended over the main shaft 102 without substantiallycontacting it due to the centering pressures applied by the poweradjusters 122A, 122B, 122C.

Referring in particular to FIG. 2, a shifting member 160, such as aninflexible rod, is slidingly engaged to an inner passage of the mainshaft 102. Two extensions 162, 164 perpendicularly extend from theshifting member 160 through an opening 165 in the main shaft 102. Afirst end 161 of the shifting member 160 proximate to the drive side ofthe transmission 100 is connected to a linkage 163, such as a cable. Thelinkage 163 is connected at an end opposite to the main shaft 102 to ashifting actuator (not shown). A tension member 202, such as a spring,is connected to a second end of the shifting member 160 by a fastener204.

Still referring in particular to FIG. 2, the extensions 162, 164 connectto the ratio changer 166. The ratio changer 166 includes a planarplatform 168 and a plurality of legs 171A, 171B, 171C whichperpendicularly extend from a surface of the platform 168 proximate tothe support member 154. The leg 171A includes two linkage pins 172A,173A. Similarly, the leg 171B includes two linkage pins 172B and 173B,and the leg 171C includes two linkage pins 172C and 173C. The linkagepins 172A, 172B, 172C, and the linkage pins 173A, 173B, 173C are used tocouple the ratio changer 166 to each of the pivot supports 134A, 134B,and 134C.

In regard to the coupling of the support 134A and the ratio changer 166,the linkage pin 172A engages an end of the leg 137A of the support 134Aopposite the pivot ring 136A, and the linkage pin 172B engages an end ofthe leg 135A opposite the pivot ring 136A. Further, in regard to thecoupling between the pivot support 134B and the ratio changer 166, thelinkage pin 173B engages an end of the leg 137B opposite the pivot ring136B, and the linkage pin 172C engages an end of the leg 135B oppositethe pivot ring 136B. Finally, in regard to the coupling between thepivot support 134C and the ratio changer 166, the linkage pin 173Cengages an end of the leg 137C opposite the pivot ring 136C, and thelinkage pin 173A engages an end of the leg 137B opposite the pivot ring136C.

Although only three power adjusters 122A, 122B, 122C are disclosed, thetransmission 100 of the invention may be configured with fewer (e.g., 2)or more (e.g., 4, 5, 6 or more) power adjusters. Further, the number oflegs on the ratio changer 166, the number of legs on the stationarysupport 152, the number of immobilizers, the number of pivot supports inthe transmission may all be correspondingly adjusted according to thenumber of power adjusters that are employed.

Referring again in general to FIGS. 1-4, a rotatable driven member 170is rotatably engaged to the main shaft 102 proximate to the ratiochanger 166 (FIG. 2). The rotatable driven member 170 is in frictionalcontact with each of the power adjusters 122A, 122B, 122C. A surface 174of the rotatable driven member 170 opposite the power adjusters 122A,122B, 122C, includes a plurality of shallow grooves 176. The rotatabledriven member 170 is in frictional coaxial contact with a second tensioninducer 178 (FIG. 2), such as a spring, and a second roller cageassembly 180 that is similar in design to the roller cage assembly 110.The second tension inducer 178 (FIG. 2) and the second roller cageassembly 180 are rotatably disposed over the main shaft 102. A hubdriver 186 (FIG. 4) is rotatably disposed over the main shaft 102 andcoaxially engaged to a side of the second roller cage assembly 180opposite the rotatable driven member 170. The hub driver 186 (FIG. 4)may be affixed to a hub shell 302 (FIGS. 3 and 4) using any traditionalgearing mechanism. In one embodiment of the invention, the hub driver186 extends proximate to the hub shell 302 and is connected to a one wayrotatable driver 300, such as a one way roller clutch. The one wayrotatable driver 300 (FIGS. 3 and 4) is rotatably coupled to the hubshell 302 (FIGS. 3 and 4).

Note that the power adjusters 122A, 122B, 122C are suspended in tightthree-point frictional contact with the drive member 120, the supportmember 154, and the driven member 170.

The hub shell 302 (FIGS. 3 and 4) has a plurality of holes 304 (FIG. 3)which provide a means for attaching the hub shell 302 to a wheel,propeller or other propulsion means. The hub shell 302 is supported andis free to rotate on the main shaft 102 by means of hub bearings 410(FIG. 4) which fit into slots in the hub driver 186. A washer 412 (FIG.4) is affixed to the main shaft 102 proximate to a side of the hubdriver 186 opposite the second roller cage assembly 180 to facilitatethe rotation of the hub bearings 410 (FIG. 4).

FIGS. 5 and 6 are a cutaway side elevational views of the transmissionof FIG. 1 illustrating the transmission of FIG. 1 in two differentshifted positions. With reference to FIGS. 5 and 6, a method of shiftingthe transmission 100 is disclosed below.

Upon an input force, the drive sleeve 104 begins to rotate in aclockwise direction. (It should be noted that the transmission 100 isalso designed to be driven in a counter-clockwise direction.) At thebeginning of the rotation of the drive sleeve 104, nominal axialpressure is supplied by the tension inducers 118, 178 (FIG. 2) to ensurethat the rotatable driving member 120, the rotatable driven member 170,and the support member 154 are in tractive contact with the poweradjusters 122A, 122B, 122C.

The rotation of the drive sleeve 104 in a clockwise direction engagesthe first roller cage assembly 110 to rotate in a similar direction. Ata low torque, the rollers 112 remain centered between the shallowgrooves 108, 109 of the rotatable driving member 120 and the drivesleeve 104. As additional torque is applied, the rollers 112 ride up thesloping sides of the grooves 108 and force the drive sleeve 104 and therotatable driving member 120 farther apart. The same action occurs onthe opposite end of the transmission 100 wherein the rotatable drivenmember 170 engages the hub driver 186 though the second roller cageassembly 180. Thus, the first roller cage assembly 110 and second rollercage assembly 180 compress the rotatable driving member 120 and therotatable driven member 170 together against the power adjusters 122A,122B, 122C, which increases the frictional contact of the poweradjusters 122A, 122B, 122C against the support member 154, the drivemember 120, and the driven member 170.

As the first rotatable driving member 120 is rotated in a clockwisedirection by the roller cage assembly 110, the roller cage assembly 110frictionally rotates the power adjusters 122A, 122B, 122C. The clockwiserotation of the power adjusters 122A, 122B, 122C causes a clockwiserotation of the rotatable driven member 170. The clockwise rotation ofthe rotatable driven member 170 engages the second roller cage assembly180 to rotate in a clockwise direction. In turn, the clockwise rotationof the second roller cage assembly 180 engages the hub driver 186 (FIG.4) to drive in a clockwise direction. The clockwise rotation of the hubdriver 186 causes the one way rotatable driver 300 to rotate clockwise.The one way rotatable driver 300 then drives the hub shell 302 (FIGS. 3and 4) to rotate in a clockwise direction.

The shifting member 160 is used to modify the axis of a rotation for thepower adjusters 122A, 122B, 122C. To shift the transmission 100, theshifting actuator (not shown) slides the shifting member 160 in a firstdirection 500 (FIG. 5). A release in tension of the linkage 163 by theshifting actuator (not shown) causes the shifting member 160 to slide ina second and opposite direction 600 (FIG. 6) by the tension member 202.The particular construction of the present transmission 100 provides formuch easier shifting than prior art traction roller designs.

When the shifting member 160 is moved in either direction by a user, theextensions 162, 164 engage the ratio changer 166 to axially move acrossthe main shaft 102. Referring to FIG. 5, when the shifting member 160 ismoved, the ratio changer 166 pivots the supports 134A, 134B, 134C. Thepivoting of the supports 134A, 134B, 134C tilts the ball spindles 130A,130B, 130C and changes the axis of rotation of each of the poweradjusters 122A, 122B, and 122C. When the shifting member 160 is moved inthe direction 500, the axis of rotation of each of the power adjusters122A, 122B, 122C is modified such that the rotatable driving member 120contacts a surface of power adjuster, 120A, 120B, 120C closer to theaxis of rotation of the power adjusters 120A, 120B, 120C. Further, therotatable driven member 170 contacts the power adjuster at a point on asurface of the each of the power adjusters 120A, 120B, 120C further awayfrom the axis of rotation of the power adjusters 120A, 120B, 120C. Theadjustment of the axis of rotation for the power adjusters 122A, 122B,122C increases an output angular velocity for the transmission 100because for every revolution of the rotatable driving member 120, therotatable driven member 170 rotates more than once.

Referring to FIG. 6, the transmission 100 of the invention is shown in aposition which causes a decrease in the output angular velocity for thetransmission 100. As the shifting member 160 is directed in thedirection 600, opposite the first direction 500, the axis of rotation ofeach of the power adjusters 122A, 122B, 122C is modified such that therotatable driven member 170 contacts a surface of each of the poweradjusters 122A, 122B, 122C closer to the axis of rotation of each of thepower adjusters 122A, 122B, 122C. Further, the rotatable driving member120 contacts each of the power adjusters 122A, 122B, 122C at a point ona surface of each of the power adjusters 122A, 122B, 122C further awayfrom the axis of rotation of each of the power adjusters 122A, 122B,122C. The adjustment of the axis of rotation for the power adjusters122A, 122B, 122C decreases an output angular velocity for thetransmission 100 because for every revolution of the rotatable drivingmember 120, the rotatable driven member 170 rotates less than once.

FIGS. 7 and 8 illustrate an automatic transmission 700 of the presentinvention. For purposes of simplicity of description, only thedifferences between the transmission 100 of FIGS. 1-6 and the automatictransmission 700 are described. FIG. 7 is a partial end elevational viewof the transmission 700, and FIG. 8 is partial side elevational view ofthe transmission 700.

A plurality of tension members 702A, 702B, 702C, which may each be aspring, interconnect each of the pivot rings 136A, 136B, 136C. Thetension member 702A is connected at a first end to the pivot ring 136Aand at a second end opposite the first end to the pivot ring 136B.Further, the tension member 702B is connected at a first end to thepivot ring 136B proximate to the aperture 138B and at a second endopposite the first end to the pivot ring 136C proximate to the aperture138C. Further, the tension member 702C is connected at a first end tothe pivot ring 136C proximate to the aperture 138C and at a second endopposite the first end to the pivot ring 136A proximate to the aperture138A.

The transmission 700 also includes flexible extension members 708A,708B, 708C respectively connected at a first end to the pivot rings136A, 136B, 136C. The transmission 700 also includes a first annularbearing 806 and a second annular bearing 816 to assist in the shiftingof the transmission 700. The first annular bearing 806 is slidinglyattached to the hub shell 302 such that first the annular bearing 806can further be directed toward the rotatable driving member 120 or therotatable driven member 170. The second annular bearing 816 also isconfigured to be slid toward either the rotatable driving member 120 orthe rotatable driven member 170; however, the second annular bearing 816is not rotatable about the main shaft 102, unlike the first annularbearing 806. The first annular bearing 806 and the second annularbearing 816 supports multiple bearing balls 808. A second end of eachthe extension members 708A, 708B, 708C connects to the second annularbearing 816 (FIG. 8).

Multiple extension members 718A, 718B, 718C respectively connect thefirst annular bearing 806 to multiple weights 720A, 720B, 720C.Optionally, a plurality of pulleys 822 may be used to route theextension members 718A, 718B, 718C from the second annular bearing 816to the weights 720A, 720B, 720C, and route the extension members 708A,708B, 708C to the first annular bearing 806.

Still referring to FIGS. 7 and 8, a method of operation for thetransmission 700 is disclosed. Similar to the embodiment of theinvention disclosed in FIG. 1, a clockwise input torque causes clockwiserotation of the drive sleeve 104, the first roller cage assembly 110,and the rotatable driving member 120. The rotatable driving member 120engages the power adjusters 122A, 122B, 122C to rotate, and therebydrives the rotatable driven member 170. The rotation of the rotatabledriven member 170 drives the second roller cage assembly 180 andproduces an output torque.

However, to be distinguished from the transmission 100 illustrated inFIG. 1, the ratio of rotation between the rotatable driving member 120and the rotatable driven member 170 is adjusted automatically by acentrifugal outward movement of the weights 720A, 720B, 720C. As theweights 720A, 720B, 720C extend outwardly, the extensions 718A, 718B,718C pull the first annular bearing 806 toward the rotatable drivingmember 120. The movement of the first annular bearing 806 toward therotatable driving member 120 similarly causes the movement of thebearings 808 and the second annular bearing 816 toward the rotatabledriving member 120.

The movement of the first annular bearing 806 toward the rotatabledriving member 120 causes the extension members 708A, 708B, 708C torespectively pivot the pivot rings 306A, 306B, 306C and adjust the axisof rotation of each of the power adjusters 122A, 122B, 122C. After theadjustment, the rotatable driven member 170 contacts a surface of poweradjusters 120A, 120B, 120C closer to the axis of rotation of each of thepower adjuster 122A, 122B, 122C. Conversely, the rotatable drivingmember 120 contacts the power adjusters 122A, 122B, 122C at a point on asurface of the each of the power adjusters 122A, 122B, 122C further awayfrom the axis of rotation of the power adjusters 122A, 122B, 122C. Theadjustment of the axis of rotation for the power adjusters 122A, 122B,122C decreases an output angular velocity for the transmission 100because for every revolution of the rotatable driving member 120, therotatable driven member 170 rotates less than once. When the hub shell302 rotates more slowly, the compression members 702A, 702B, 702C adjustthe axis of rotation of the power adjusters 122A, 122B, 122C to provideto a lower output angular velocity in comparison to the input angularvelocity.

FIGS. 9 and 10 illustrate an alternative embodiment of the invention.For purposes of simplicity of description, only the differences betweenthe transmission 100 of FIG. 1 and a transmission 900 of FIGS. 9 and 10are described. FIG. 9 is a partial end elevational view of thetransmission 900, and FIG. 10 is partial side elevational view of thetransmission 900.

The transmission 900 includes flexible extension members 908A, 908B,908C respectively connected at a first end to the pivot rings 136A,136B, 136C. A second end of the extension members 908A, 908B, 908Cconnects to a synchronization member 912. Further each of the extensionmembers 908A, 908B, 908C are slidingly engaged to a plurality of pulleys916 (FIG. 9) which are affixed to the hub shell 302. It is noted thatthe number and location of the each of the pulleys 916 (FIG. 9) may bevaried. For example, a different pulley configuration may be used toroute the extension members 908A, 908B, 908C depending on the selectedframe of the machine or vehicle that employs the transmission 900.Additionally, the pulleys 916 and extension members 908A, 908B, 908C maybe located inside the hub shell 302.

The hub shell 302 of the transmission 900 is non-rotational. Further,the hub shell 302 includes a plurality of apertures (not shown) whichare used to guide the extension members 908A, 908B, 908C to thesynchronization member 912.

To be noted, according to the embodiment of the invention illustrated inFIGS. 9 and 10, the shifting assembly of the transmission 100 of FIG. 2may be eliminated, including the main shaft 102 (FIG. 2), the tensionmember 202 (FIG. 2), the extensions 162, 164 (FIG. 2) and the shiftingactuator (not shown).

Still referring to FIGS. 9 and 10, a method of operation for thetransmission 900 is disclosed. Similar to the embodiment of theinvention disclosed in FIG. 1, an input torque causes a clockwiserotation of the drive sleeve 104, the first roller cage assembly 110,and the rotatable driving member 120. The rotatable driving member 120engages the power adjusters 122A, 122B, 122 to rotate, and thereby drivethe rotatable driven member 170. The rotation of the rotatable drivenmember 170 drives the second roller cage assembly 180 and produces anoutput torque.

In the transmission 900, the ratio of rotation between the rotatabledriving member 120 and the rotatable driven member 170 is adjusted bythe manipulation of the synchronization member 912. As thesynchronization member 912 is outwardly directed from the hub shell 302,the extension members 908A, 908B, 908C respectively pivot the pivotrings 136A, 136B, 136C such that the axis of rotation of each of thepower adjusters 122A, 122B, and 122C is similarly pivoted. The axis ofrotation of each of the power adjusters 122A, 122B, 122C is modifiedsuch that the rotatable driving member 120 contacts a surface of poweradjusters 122A, 122B, 122C further away from the axis of rotation ofeach of the power adjusters 122A, 122B, 122C. Conversely, the rotatabledriven member 170 contacts the power adjusters 122A, 122B, 122C at apoint on a surface of the each of the power adjusters 122A, 122B, 122Ccloser to the axis of rotation of each of the power adjusters 122A,122B, 122C. The adjustment of the axis of rotation for the poweradjusters 122A, 122B, 122C decreases an output angular velocity for thetransmission 100 because for every revolution of the rotatable drivingmember 120, the rotatable driven member 170 rotates less than once.

When the synchronization member 912 is directed toward the hub shell302, the tension members 702A, 702B, 702C compress. This compressioncauses an end of the pivot rings 136A, 136B, 136C proximate to therotatable driven member 170 to pivot toward the main shaft 102. Thepivoting of the pivot rings 136A, 136B, 136C causes the axis of rotationof each of the power adjusters 122A, 122B, 122C to be modified such thatthe rotatable driven member 170 rotates slower than the rotatabledriving member 120.

FIG. 11 illustrates another alternative embodiment of the inventionincluding a transmission 1100 having a first thrust bearing 1106 and asecond thrust bearing 1108. The first thrust bearing 1106 is rotatablydisposed over the main shaft 102 and is positioned between the supportmember 154 and the extensions 162, 164. The second thrust bearing 1108is disposed over the main shaft 102 on a side of the support member 154opposite the first thrust bearing 1106. The transmission 1100 mayoptionally also include a second ratio changer, such as ratio changer1110, which is disposed over the main shaft 102 and is axially slidable.

When the ratio changers 166, 1110 slide axially to cause a shift in thetransmission 1100, the ratio changers 166, 1110 also slide the thrustbearings 1106, 1108. The sliding of the thrust bearings 1106, 1108forces the support member 154 to slide in unison with the ratio changers166, 1110. A small amount of play is provided between the support member154 and the thrust bearings 1106, 1008 so that the thrust bearings 1106,1108 do not contact the support member 154 except when the transmission1100 is in the process of shifting.

FIG. 12 illustrates an alternative embodiment of the invention. FIG. 12illustrates a transmission 1200 that operates similarly to theembodiment of the invention disclosed in FIG. 10; however, thetransmission 1200 of FIG. 12 includes two rotatable drivers 1204, 1206and a rotatable driving shaft 1212. The rotatable driving shaft 1212 isfixedly attached to the drive sleeve 104.

Still referring to FIG. 12, the first rotatable driver 1204 includes aone way clutch 1208 that is configured to rotate the rotatable drivingshaft 1212 upon the rotation of the rotatable driver in a firstdirection. The second rotatable driver 1206 includes a one way clutch1210. The second rotatable driver 1206 is configured to engage the drivesleeve 104 upon the rotation of the second rotatable driver 1206 in asecond direction, which is opposite to the activation direction of thefirst rotatable driver 1204. The second rotatable driver 1206 is fixedlyattached to the drive sleeve 104.

FIG. 13 schematically illustrates another alternative embodiment of theinvention having a transmission 1300 that is configured to shiftautomatically. Three pulleys 1306, 1308, 1310 are respectively connectedto the pivot rings 136A, 136B, and 136C. A cable 1312 is guided aroundthe pulley 1306 and connects at a first end to the main shaft 102 andconnects at a second end to an annular ring (not shown), similar to theannular ring 816 of FIG. 8. Similarly, a cable 1314 is guided around thepulley 1308 and connects to the main shaft 102 at a first end andconnects at a second end to the annular ring (not shown) Lastly, a cable1316 is guided around the pulley 1310 and connects at a first end to themain shaft 102 and connects at a second end to the annular ring (notshown).

FIG. 14 schematically illustrates the transmission 1300 of FIG. 13 froma front end. A plurality of tension members 1404, 1406, 1408interconnect each of the pivot rings 136A, 136B, and 136C. The tensionmember 1404 connects at a first end to the pivot ring 136A and connectsat a second end opposite the first end to the pivot ring 136B. Thetension member 1406 connects at a first end to the pivot ring 136B andconnects at a second end opposite the first end at the pivot ring 136C.The tension member 1408 connects at a first end to the pivot ring 136Aand connects at a second end opposite the first end at the pivot ring136C.

FIG. 15 schematically illustrates a housing 1500 for the transmission1300 of FIGS. 13 and 14. The housing 1500 includes three hollow guidetubes 1504, 1506, and 1508. Each of the hollow guide tubes 1504, 1506,1508 connect at a first end to a hub shell 1512 that holds thetransmission 1300 and at a second end opposite the first end to atransmission wheel 1514. Three tension members 1516, 1518, 1520 arerespectively disposed within the guide tubes 1504, 1506, 1508 and areconnected at a first end to the transmission wheel 1514. A second end ofthe tension members 1516, 1518, 1520 opposite the transmission wheel1514 are respectively connected with spherical weights 1526, 1528, 1530.In alternative embodiments of the invention, the weights 1526, 1528,1530 may be adapted to other geometric shapes.

Multiple linkage members 1532, 1534, 1536, respectively extend from theweights 1526, 1528, 1530 to an annular member (not shown), such as theannular member 806 of FIG. 8.

Turning to the method of operation of the housing 1500 of FIG. 15, therotation of the hub shell 1512 causes the rotation of the hollow guidetubes 1504, 1506, 1508. As the guide tubes 1504, 1506, 1058 rotate, theweights 1526, 1528, 1530 extend outwardly toward the transmission wheel1514. The outward movement of the weights 1526, 1528, 1530 causes ashifting of the axis of rotation of the power adjusters 122A, 122B, 122Cof FIGS. 13 and 14.

FIG. 16 is another alternative embodiment of the invention. FIG. 16 is aschematic illustration of a manual version of the transmission 1300shown in FIGS. 13 and 14. For purposes of simplicity of description,only the differences between the transmission 1600 of FIG. 16 and thetransmission 1300 of FIGS. 13 and 14 are described. The transmission1600 includes a flexible cable 1602 that connects at a first end to ashifting actuator (not shown). The cable 1602 extends from the shiftingactuator (not shown), through the central passageway of the main shaft102 and then extends through an aperture (not shown) on the main shaft102. From the aperture (not shown) the cable 1602 extends around thepulley 1308. From the pulley 1308, the cable is guided around the pulley1306. From the pulley 1306, the cable extends to the pulley 1308.Finally, from the pulley 1308, the cable 1602 connects to the main shaft102.

Still referring to FIG. 16, as the cable 1602 is directed toward theshifting actuator (not shown), the cable 1602 pulls on the pulleys 1304,1306, 1308 thereby causing a shift in the axis of rotation of each ofthe power adjusters 122A, 122B, 122C. Conversely, when the shiftingactuator (not shown) releases the cable 1602, the tension members 1404,1406, 1408 cause each of the axis of rotation of the power adjusters122A, 122B, 122C to shift in a second and opposite direction.

The present invention provides a novel transmission which provides acontinuously variable input/output angular velocity ratio offering up toa 900% range of input/output angular velocity. Further, the transmissioncan be actuated either manually or automatically.

Further, the transmission of the invention provides a simple designwhich requires a minimal number of parts to implement, and is thereforesimple to manufacture, compact, light and produces very little friction.The transmission eliminates duplicate, overlapping, or unusable gearswhich are found in geared transmissions. The transmission eliminates theneed for clutches which are traditionally used for changing gears.Lastly, the transmission can save energy or gasoline by providing anideal input to output angular speed ratio.

While the above detailed description has shown, described, and pointedout novel features of the invention as applied to various embodiments,it will be understood that various omissions, substitutions, and changesin the form and details of the device or process illustrated may be madeby those skilled in the art without departing from the spirit of theinvention. The scope of the invention is indicated by the appendedclaims rather than by the foregoing description. All changes which comewithin the meaning and range of equivalency of the claims are to beembraced within their scope.

What is claimed is:
 1. A continuously variable transmission, comprising:three or more spherical power adjusters, each power adjuster having acylindrical hole extending through its center; three or more cylindricalspindles, each spindle positioned in the hole of one power adjuster; atleast one stationary support with an aperture at its center; a rotatablesupport member having first and second sides, the rotatable supportmember located between the power adjusters and frictionally engaged withthe plurality of power adjusters, wherein the rotatable support memberhas a substantially uniform outer diameter, wherein the rotatablesupport member is capable of axial movement, and wherein the rotatablesupport member has at least two areas that are bearing surfaces tocontrol axial movement of the rotatable support member; a first annularbearing capable of axial movement, positioned on the first side of thesupport member; a second annular bearing capable of axial movement,positioned on the second side of the support member; a first planarplatform capable of axial movement, positioned so that the first annularbearing is between the rotatable support member and the first planarplatform; a second planar platform capable of axial movement, positionedso that the second annular bearing is between the rotatable support andthe second planar platform; and a ratio changer operably connected tothe cylindrical spindles, wherein an adjustment in the ratio changercauses the cylindrical spindles to change their axes of rotation.
 2. Acontinuously variable transmission, comprising: a rotatable drivingmember; three or more spherical power adjusters, each power adjusterhaving a cylindrical hole extending through its center; three or morecylindrical spindles, each spindle positioned in the hole of one poweradjuster; a drive sleeve; three or more ramped surfaces on the drivesleeve that face the rotatable driving member; three or more rollerspositioned to roll on the three or more ramped surfaces of the drivesleeve and also roll on the rotatable driving member; a roller cagepositioning the three or more rollers; the three or more ramped surfacesof the drive sleeve configured so that when the three or more rollersrotate they compress the rotatable driving member against the three ormore spherical power adjusters upon an increase in torque and decompressthe rotatable driving member upon a decrease in torque; a rotatablesupport member located between the power adjusters that has first andsecond sides, and is frictionally engaged with the three or more poweradjusters, wherein the rotatable support member has a substantiallyuniform outer diameter, wherein the rotatable support member is capableof axial movement, and wherein the rotatable support member has at leasttwo areas that are bearing surfaces to control axial movement of therotatable support member; a first annular bearing capable of axialmovement, positioned on the first side of the support member; a secondannular bearing capable of axial movement, positioned on the second sideof the support member; a first planar platform capable of axialmovement, positioned so that the first annular bearing is between therotatable support member and the first planar platform; a second planarplatform capable of axial movement, positioned so that the secondannular bearings is between the rotatable support and the second planarplatform; at least one stationary support with an aperture at itscenter; and wherein the rotatable support member, the first annularbearing, the second annular bearing, the first planar platform, and thesecond planar platform are all capable of simultaneous axial movement.3. The transmission of claim 2 wherein the ramped surfaces of the drivesleeve are linear.
 4. The transmission of claim 2 wherein the rollersare cylindrical.
 5. The transmission of claim 2, further comprising ahollow shaft and a shifting member positioned in the shaft, wherein theshifting member is configured to actuate an adjustment in an axis ofrotation of each of the power adjusters.
 6. A continuously variabletransmission, comprising: a shaft; a rotatable driving member rotatablymounted over the shaft; a rotatable driven member rotatably mounted overthe shaft; a plurality of spherical power adjusters frictionallyinterposed between the rotatable driving member and the rotatable drivenmember and adapted to transmit power from the rotatable driving memberto the rotatable driven member, each power adjuster having a cylindricalhole extending through its center; a plurality of cylindrical spindles,each spindle positioned in the hole of one power adjuster; a rotatablesupport member located between the power adjusters and frictionallyengaged with the plurality of power adjusters so that the poweradjusters each are in frictional contact with each of the drivingmember, the driven member, and the rotatable support member; a firstannular bearing positioned on a first side of the support member; asecond annular bearing positioned on a second side of the supportmember; at least one stationary support with an aperture at its center;and a plurality of legs attached to the at least one stationary support.7. The transmission of claim 6, wherein the legs are rigidly attached tothe at least one stationary support and assist holding the poweradjusters in a stationary position to prevent them from orbiting aroundthe axis of the rotatable support member.
 8. The transmission of claim7, wherein the plurality of legs extend substantially perpendicular fromthe at least one stationary support.
 9. The transmission of claim 6,wherein the shaft is hollow, and the transmission further includes ashifting member in the shaft, the shifting member configured to actuatean adjustment in an axis of rotation in each of the plurality of poweradjusters.
 10. A continuously variable transmission, comprising: arotatable driving member; three or more spherical power adjusters, eachpower adjuster having a cylindrical hole extending through its center;three or more cylindrical spindles, each spindle positioned in the holeof one power adjuster; at least one stationary support with an apertureat its center; a rotatable support member located between the poweradjusters having first and second sides, and frictionally engaged withthe plurality of power adjusters, wherein the rotatable support memberhas a substantially uniform outer diameter, wherein the rotatablesupport member is capable of axial movement, and wherein the rotatablesupport member has at least two areas that are bearing surfaces tocontrol axial movement of the rotatable support member; a first annularbearing capable of axial movement, positioned on the first side of thesupport member; a second annular bearing capable of axial movement,positioned on the second side of the support member; a first planarplatform capable of axial movement, positioned so that the first annularbearing is between the rotatable support member and the first planarplatform; a second planar platform capable of axial movement, positionedso that the second annular bearing is between the rotatable support andthe second planar platform; a shifting member, having an end thatextends outside of the transmission, that is positioned along the axisof the rotatable support member and is operably engaged with therotatable support member; and wherein an adjustment in the position ofthe shifting member causes the rotatable support member, the firstannular bearing, the second annular bearing, the first planar platform,and the second planar platform to all move simultaneously and asubstantially equal distance.
 11. The transmission of claim 10, furthercomprising a linkage having first and second ends attached at the firstend to the shifting member and at the second end to a shifting actuator.12. The transmission of claim 10, further comprising a tension memberbiasing the shifting member towards a first position.
 13. Thetransmission of claim 10, further comprising a ratio changer, the ratiochanger operably engaged with the cylindrical spindles.
 14. Thetransmission of claim 10, wherein at least one point on the surface ofeach of the power adjusters undergoes an arcuate travel in the axis ofrotation of the spindle that is longer than the axial movement of therotatable support member when the transmission is shifted.